which remains an open problem till date. However Ma [1]} proved this generalized Zalcman conjecture for classes \(\mathcal {S}^{*}\)  and \(\mathcal {S}_{\mathbb {R}}\) , where \(\mathcal {S}_{\mathbb {R}}\)  denotes
the class of
all functions in \(\mathcal {S}\)  with real coefficients.
